ESP32 DS18B20 no delay

esp32ds18b20_nodelay.ino

#include "MHDS18B20.h"

OneWire  ds(5);  // on pin D2 (a 4.7K resistor is necessary)
int  numberOfSensors;
byte currentAddr[8];

struct sensorStruct {
  byte addr[8];
} sensor[3];

byte data[12];
byte type_s;
float celsius, fahrenheit;

unsigned long sensorReadTime;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  while ( ds.search(currentAddr) ) {
    numberOfSensors++;
    Serial.write( "Sensor "); Serial.print( numberOfSensors ); Serial.print( ":" );
    for ( byte i = 0; i < 8; i++) {
      Serial.write(' ');
      Serial.print(currentAddr[i], HEX);
      sensor[numberOfSensors].addr[i] = currentAddr[i];
    }
    Serial.println();
  }

  Serial.print(numberOfSensors); Serial.println( " sensors found." );
  for ( byte thisSensor = 0; thisSensor < numberOfSensors; thisSensor++) {
    ds.reset();
    ds.select( sensor[thisSensor].addr );
    ds.write( 0x44, 1);        // start conversion, with parasite power on at the end
  }

  if ( numberOfSensors > 0 ) {
    sensorReadTime = millis() + 750;
  }

  for (byte nos = 1; nos <= numberOfSensors; nos++) {
    for ( byte i = 0; i < 8; i++) {
      Serial.write(' ');
      Serial.print( sensor[nos].addr[i], HEX );
    }
    Serial.println();
  }
}

void loop() {
  // put your main code here, to run repeatedly:
  if ( millis() >= sensorReadTime ) {
    readTemps();
  }
}

void readTemps() {
  for ( byte thisSensor = 1; thisSensor <= numberOfSensors; thisSensor++) {
    ds.reset();
    ds.select( sensor[thisSensor].addr );
    ds.write(0xBE);         // Read Scratchpad

    //Serial.print( thisSensor ); Serial.print("  Data = ");
    //Serial.print(present, HEX);
    Serial.print(" ");
    for ( byte i = 0; i < 9; i++) {           // we need 9 bytes
      data[i] = ds.read(  );
      //Serial.print(data[i], HEX);
      //Serial.print(" ");
    }
    //Serial.print(" CRC=");
    //Serial.print(OneWire::crc8(data, 8), HEX);
    //Serial.println();

    int16_t raw = (data[1] << 8) | data[0];
    if (type_s) {
      raw = raw << 3; // 9 bit resolution default
      if (data[7] == 0x10) {
        // "count remain" gives full 12 bit resolution
        raw = (raw & 0xFFF0) + 12 - data[6];
      }
    } else {
      byte cfg = (data[4] & 0x60);
      // at lower res, the low bits are undefined, so let's zero them
      if (cfg == 0x00) raw = raw & ~7;  // 9 bit resolution, 93.75 ms
      else if (cfg == 0x20) raw = raw & ~3; // 10 bit res, 187.5 ms
      else if (cfg == 0x40) raw = raw & ~1; // 11 bit res, 375 ms
      //// default is 12 bit resolution, 750 ms conversion time
    }
    celsius = (float)raw / 16.0;
    fahrenheit = celsius * 1.8 + 32.0;

    Serial.print("  Temperature = ");

    Serial.print(celsius);
    Serial.print(" Celsius");
    Serial.println();

  ds.reset();
  ds.select( sensor[thisSensor].addr  );    
  ds.write( 0x44, 1);        // start conversion, with parasite power on at the end
  }

  sensorReadTime = millis() + 750;
}